The present invention is directed to a display unit for digital presentation of motor vehicle operational data and includes at least one switch for continuous scanning of the available operational data and another switch for erasing operational data concerned with a particular part of a vehicle trip.
A display unit of the above type provides operational data in a motor vehicle not available, or not available in sufficient detail from the conventional vehicle instrumentation indicating speed, RPM, fuel and engine temperature. In providing such data, the space available, in the visible range of the driver, is not sufficient for separate display units and it would not be desirable for aesthetic and practical reasons to house a variety of the display units on the instrumentation panel on a dashboard. Further, it is preferable if certain operational data is not continuously displayed, but rather can be scanned when required. If the operational data is used to assist in economical operation of the vehicle, then the data required would be momentary fuel consumption, average fuel consumption, average speed, as well as the distance travelled and the elapsed trip time.
If such a display unit is to be successful, it must be arranged within the visual field of the operator and, in particular, must be installed in the dashboard, that is, the space where the conventional vehicle instrumentation is located and where the additional available space is limited. Moreover, the dimensions of the display unit must correspond to an area on the dashboard selected for reasons of design.
Due to the available space on a dashboard, a display unit of relatively small dimension is required. On the other hand, an easily readable display is needed so that the information can be obtained at a glance and the display is such that it does not divert the driver's attention from traffic conditions and, at the same time, affords a visible display as large as possible.
These contradictory requirements leave very little room for the means for operating the display device. In the known state of the art, at least two keys or buttons are required and they must be arranged in close proximity to one another and with relatively small operating surfaces.
Such an arrangement of the operating means is not very convenient for the vehicle driver, since operation of the unit must take place while driving and without any conscious monitoring of the operating means.